tools/lib/bpf/libbpf.h

   1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
   2
   3 /*
   4  * Common eBPF ELF object loading operations.
   5  *
   6  * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
   7  * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
   8  * Copyright (C) 2015 Huawei Inc.
   9  */
  10 #ifndef __LIBBPF_LIBBPF_H
  11 #define __LIBBPF_LIBBPF_H
  12
  13 #include <stdarg.h>
  14 #include <stdio.h>
  15 #include <stdint.h>
  16 #include <stdbool.h>
  17 #include <sys/types.h>  // for size_t
  18 #include <linux/bpf.h>
  19
  20 #include "libbpf_common.h"
  21
  22 #ifdef __cplusplus
  23 extern "C" {
  24 #endif
  25
  26 enum libbpf_errno {
  27         __LIBBPF_ERRNO__START = 4000,
  28
  29         /* Something wrong in libelf */
  30         LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
  31         LIBBPF_ERRNO__FORMAT,   /* BPF object format invalid */
  32         LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */
  33         LIBBPF_ERRNO__ENDIAN,   /* Endian mismatch */
  34         LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */
  35         LIBBPF_ERRNO__RELOC,    /* Relocation failed */
  36         LIBBPF_ERRNO__LOAD,     /* Load program failure for unknown reason */
  37         LIBBPF_ERRNO__VERIFY,   /* Kernel verifier blocks program loading */
  38         LIBBPF_ERRNO__PROG2BIG, /* Program too big */
  39         LIBBPF_ERRNO__KVER,     /* Incorrect kernel version */
  40         LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */
  41         LIBBPF_ERRNO__WRNGPID,  /* Wrong pid in netlink message */
  42         LIBBPF_ERRNO__INVSEQ,   /* Invalid netlink sequence */
  43         LIBBPF_ERRNO__NLPARSE,  /* netlink parsing error */
  44         __LIBBPF_ERRNO__END,
  45 };
  46
  47 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
  48
  49 enum libbpf_print_level {
  50         LIBBPF_WARN,
  51         LIBBPF_INFO,
  52         LIBBPF_DEBUG,
  53 };
  54
  55 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
  56                                  const char *, va_list ap);
  57
  58 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
  59
  60 /* Hide internal to user */
  61 struct bpf_object;
  62
  63 struct bpf_object_open_attr {
  64         const char *file;
  65         enum bpf_prog_type prog_type;
  66 };
  67
  68 struct bpf_object_open_opts {
  69         /* size of this struct, for forward/backward compatiblity */
  70         size_t sz;
  71         /* object name override, if provided:
  72          * - for object open from file, this will override setting object
  73          *   name from file path's base name;
  74          * - for object open from memory buffer, this will specify an object
  75          *   name and will override default "<addr>-<buf-size>" name;
  76          */
  77         const char *object_name;
  78         /* parse map definitions non-strictly, allowing extra attributes/data */
  79         bool relaxed_maps;
  80         /* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures.
  81          * Value is ignored. Relocations always are processed non-strictly.
  82          * Non-relocatable instructions are replaced with invalid ones to
  83          * prevent accidental errors.
  84          * */
  85         bool relaxed_core_relocs;
  86         /* maps that set the 'pinning' attribute in their definition will have
  87          * their pin_path attribute set to a file in this directory, and be
  88          * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
  89          */
  90         const char *pin_root_path;
  91         __u32 attach_prog_fd;
  92         /* Additional kernel config content that augments and overrides
  93          * system Kconfig for CONFIG_xxx externs.
  94          */
  95         const char *kconfig;
  96 };
  97 #define bpf_object_open_opts__last_field kconfig
  98
  99 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
 100 LIBBPF_API struct bpf_object *
 101 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
 102 LIBBPF_API struct bpf_object *
 103 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
 104                      const struct bpf_object_open_opts *opts);
 105
 106 /* deprecated bpf_object__open variants */
 107 LIBBPF_API struct bpf_object *
 108 bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
 109                         const char *name);
 110 LIBBPF_API struct bpf_object *
 111 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
 112
 113 enum libbpf_pin_type {
 114         LIBBPF_PIN_NONE,
 115         /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
 116         LIBBPF_PIN_BY_NAME,
 117 };
 118
 119 /* pin_maps and unpin_maps can both be called with a NULL path, in which case
 120  * they will use the pin_path attribute of each map (and ignore all maps that
 121  * don't have a pin_path set).
 122  */
 123 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
 124 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
 125                                       const char *path);
 126 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
 127                                         const char *path);
 128 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
 129                                           const char *path);
 130 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
 131 LIBBPF_API void bpf_object__close(struct bpf_object *object);
 132
 133 struct bpf_object_load_attr {
 134         struct bpf_object *obj;
 135         int log_level;
 136         const char *target_btf_path;
 137 };
 138
 139 /* Load/unload object into/from kernel */
 140 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
 141 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
 142 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
 143
 144 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
 145 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
 146
 147 struct btf;
 148 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
 149 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
 150
 151 LIBBPF_API struct bpf_program *
 152 bpf_object__find_program_by_title(const struct bpf_object *obj,
 153                                   const char *title);
 154 LIBBPF_API struct bpf_program *
 155 bpf_object__find_program_by_name(const struct bpf_object *obj,
 156                                  const char *name);
 157
 158 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev);
 159 #define bpf_object__for_each_safe(pos, tmp)                     \
 160         for ((pos) = bpf_object__next(NULL),            \
 161                 (tmp) = bpf_object__next(pos);          \
 162              (pos) != NULL;                             \
 163              (pos) = (tmp), (tmp) = bpf_object__next(tmp))
 164
 165 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
 166 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
 167                                     bpf_object_clear_priv_t clear_priv);
 168 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
 169
 170 LIBBPF_API int
 171 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
 172                          enum bpf_attach_type *expected_attach_type);
 173 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
 174                                           enum bpf_attach_type *attach_type);
 175 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
 176                                           enum bpf_attach_type attach_type);
 177
 178 /* Accessors of bpf_program */
 179 struct bpf_program;
 180 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog,
 181                                                  const struct bpf_object *obj);
 182
 183 #define bpf_object__for_each_program(pos, obj)          \
 184         for ((pos) = bpf_program__next(NULL, (obj));    \
 185              (pos) != NULL;                             \
 186              (pos) = bpf_program__next((pos), (obj)))
 187
 188 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog,
 189                                                  const struct bpf_object *obj);
 190
 191 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
 192
 193 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
 194                                      bpf_program_clear_priv_t clear_priv);
 195
 196 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
 197 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 198                                          __u32 ifindex);
 199
 200 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
 201 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
 202                                           bool needs_copy);
 203
 204 /* returns program size in bytes */
 205 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
 206
 207 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
 208                                  __u32 kern_version);
 209 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
 210 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
 211                                          const char *path,
 212                                          int instance);
 213 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
 214                                            const char *path,
 215                                            int instance);
 216 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
 217 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
 218 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
 219
 220 struct bpf_link;
 221
 222 LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
 223 LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
 224 LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
 225 LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
 226 LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
 227 LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
 228                                         struct bpf_program *prog);
 229 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
 230 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
 231
 232 LIBBPF_API struct bpf_link *
 233 bpf_program__attach(struct bpf_program *prog);
 234 LIBBPF_API struct bpf_link *
 235 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
 236 LIBBPF_API struct bpf_link *
 237 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
 238                            const char *func_name);
 239 LIBBPF_API struct bpf_link *
 240 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
 241                            pid_t pid, const char *binary_path,
 242                            size_t func_offset);
 243 LIBBPF_API struct bpf_link *
 244 bpf_program__attach_tracepoint(struct bpf_program *prog,
 245                                const char *tp_category,
 246                                const char *tp_name);
 247 LIBBPF_API struct bpf_link *
 248 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
 249                                    const char *tp_name);
 250 LIBBPF_API struct bpf_link *
 251 bpf_program__attach_trace(struct bpf_program *prog);
 252 LIBBPF_API struct bpf_link *
 253 bpf_program__attach_lsm(struct bpf_program *prog);
 254 LIBBPF_API struct bpf_link *
 255 bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd);
 256
 257 struct bpf_map;
 258
 259 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map);
 260
 261 struct bpf_insn;
 262
 263 /*
 264  * Libbpf allows callers to adjust BPF programs before being loaded
 265  * into kernel. One program in an object file can be transformed into
 266  * multiple variants to be attached to different hooks.
 267  *
 268  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
 269  * form an API for this purpose.
 270  *
 271  * - bpf_program_prep_t:
 272  *   Defines a 'preprocessor', which is a caller defined function
 273  *   passed to libbpf through bpf_program__set_prep(), and will be
 274  *   called before program is loaded. The processor should adjust
 275  *   the program one time for each instance according to the instance id
 276  *   passed to it.
 277  *
 278  * - bpf_program__set_prep:
 279  *   Attaches a preprocessor to a BPF program. The number of instances
 280  *   that should be created is also passed through this function.
 281  *
 282  * - bpf_program__nth_fd:
 283  *   After the program is loaded, get resulting FD of a given instance
 284  *   of the BPF program.
 285  *
 286  * If bpf_program__set_prep() is not used, the program would be loaded
 287  * without adjustment during bpf_object__load(). The program has only
 288  * one instance. In this case bpf_program__fd(prog) is equal to
 289  * bpf_program__nth_fd(prog, 0).
 290  */
 291
 292 struct bpf_prog_prep_result {
 293         /*
 294          * If not NULL, load new instruction array.
 295          * If set to NULL, don't load this instance.
 296          */
 297         struct bpf_insn *new_insn_ptr;
 298         int new_insn_cnt;
 299
 300         /* If not NULL, result FD is written to it. */
 301         int *pfd;
 302 };
 303
 304 /*
 305  * Parameters of bpf_program_prep_t:
 306  *  - prog:     The bpf_program being loaded.
 307  *  - n:        Index of instance being generated.
 308  *  - insns:    BPF instructions array.
 309  *  - insns_cnt:Number of instructions in insns.
 310  *  - res:      Output parameter, result of transformation.
 311  *
 312  * Return value:
 313  *  - Zero:     pre-processing success.
 314  *  - Non-zero: pre-processing error, stop loading.
 315  */
 316 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
 317                                   struct bpf_insn *insns, int insns_cnt,
 318                                   struct bpf_prog_prep_result *res);
 319
 320 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
 321                                      bpf_program_prep_t prep);
 322
 323 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
 324
 325 /*
 326  * Adjust type of BPF program. Default is kprobe.
 327  */
 328 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
 329 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
 330 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
 331 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
 332 LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
 333 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
 334 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
 335 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
 336 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
 337 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
 338 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
 339 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
 340
 341 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
 342 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
 343                                       enum bpf_prog_type type);
 344
 345 LIBBPF_API enum bpf_attach_type
 346 bpf_program__get_expected_attach_type(struct bpf_program *prog);
 347 LIBBPF_API void
 348 bpf_program__set_expected_attach_type(struct bpf_program *prog,
 349                                       enum bpf_attach_type type);
 350
 351 LIBBPF_API int
 352 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
 353                                const char *attach_func_name);
 354
 355 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
 356 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
 357 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
 358 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
 359 LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
 360 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
 361 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
 362 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
 363 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
 364 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
 365 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
 366 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
 367
 368 /*
 369  * No need for __attribute__((packed)), all members of 'bpf_map_def'
 370  * are all aligned.  In addition, using __attribute__((packed))
 371  * would trigger a -Wpacked warning message, and lead to an error
 372  * if -Werror is set.
 373  */
 374 struct bpf_map_def {
 375         unsigned int type;
 376         unsigned int key_size;
 377         unsigned int value_size;
 378         unsigned int max_entries;
 379         unsigned int map_flags;
 380 };
 381
 382 /*
 383  * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
 384  * so no need to worry about a name clash.
 385  */
 386 LIBBPF_API struct bpf_map *
 387 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
 388
 389 LIBBPF_API int
 390 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
 391
 392 /*
 393  * Get bpf_map through the offset of corresponding struct bpf_map_def
 394  * in the BPF object file.
 395  */
 396 LIBBPF_API struct bpf_map *
 397 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
 398
 399 LIBBPF_API struct bpf_map *
 400 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
 401 #define bpf_object__for_each_map(pos, obj)              \
 402         for ((pos) = bpf_map__next(NULL, (obj));        \
 403              (pos) != NULL;                             \
 404              (pos) = bpf_map__next((pos), (obj)))
 405 #define bpf_map__for_each bpf_object__for_each_map
 406
 407 LIBBPF_API struct bpf_map *
 408 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
 409
 410 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
 411 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
 412 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
 413 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
 414 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
 415
 416 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
 417 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
 418                                  bpf_map_clear_priv_t clear_priv);
 419 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
 420 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
 421                                           const void *data, size_t size);
 422 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
 423 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
 424 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
 425 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
 426 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 427 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
 428 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
 429 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
 430 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
 431 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
 432
 433 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
 434
 435 LIBBPF_API long libbpf_get_error(const void *ptr);
 436
 437 struct bpf_prog_load_attr {
 438         const char *file;
 439         enum bpf_prog_type prog_type;
 440         enum bpf_attach_type expected_attach_type;
 441         int ifindex;
 442         int log_level;
 443         int prog_flags;
 444 };
 445
 446 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 447                                    struct bpf_object **pobj, int *prog_fd);
 448 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
 449                              struct bpf_object **pobj, int *prog_fd);
 450
 451 struct xdp_link_info {
 452         __u32 prog_id;
 453         __u32 drv_prog_id;
 454         __u32 hw_prog_id;
 455         __u32 skb_prog_id;
 456         __u8 attach_mode;
 457 };
 458
 459 struct bpf_xdp_set_link_opts {
 460         size_t sz;
 461         __u32 old_fd;
 462 };
 463 #define bpf_xdp_set_link_opts__last_field old_fd
 464
 465 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
 466 LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
 467                                         const struct bpf_xdp_set_link_opts *opts);
 468 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
 469 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
 470                                      size_t info_size, __u32 flags);
 471
 472 struct perf_buffer;
 473
 474 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
 475                                       void *data, __u32 size);
 476 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
 477
 478 /* common use perf buffer options */
 479 struct perf_buffer_opts {
 480         /* if specified, sample_cb is called for each sample */
 481         perf_buffer_sample_fn sample_cb;
 482         /* if specified, lost_cb is called for each batch of lost samples */
 483         perf_buffer_lost_fn lost_cb;
 484         /* ctx is provided to sample_cb and lost_cb */
 485         void *ctx;
 486 };
 487
 488 LIBBPF_API struct perf_buffer *
 489 perf_buffer__new(int map_fd, size_t page_cnt,
 490                  const struct perf_buffer_opts *opts);
 491
 492 enum bpf_perf_event_ret {
 493         LIBBPF_PERF_EVENT_DONE  = 0,
 494         LIBBPF_PERF_EVENT_ERROR = -1,
 495         LIBBPF_PERF_EVENT_CONT  = -2,
 496 };
 497
 498 struct perf_event_header;
 499
 500 typedef enum bpf_perf_event_ret
 501 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
 502
 503 /* raw perf buffer options, giving most power and control */
 504 struct perf_buffer_raw_opts {
 505         /* perf event attrs passed directly into perf_event_open() */
 506         struct perf_event_attr *attr;
 507         /* raw event callback */
 508         perf_buffer_event_fn event_cb;
 509         /* ctx is provided to event_cb */
 510         void *ctx;
 511         /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
 512          * max_entries of given PERF_EVENT_ARRAY map)
 513          */
 514         int cpu_cnt;
 515         /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
 516         int *cpus;
 517         /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
 518         int *map_keys;
 519 };
 520
 521 LIBBPF_API struct perf_buffer *
 522 perf_buffer__new_raw(int map_fd, size_t page_cnt,
 523                      const struct perf_buffer_raw_opts *opts);
 524
 525 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
 526 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
 527
 528 typedef enum bpf_perf_event_ret
 529         (*bpf_perf_event_print_t)(struct perf_event_header *hdr,
 530                                   void *private_data);
 531 LIBBPF_API enum bpf_perf_event_ret
 532 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
 533                            void **copy_mem, size_t *copy_size,
 534                            bpf_perf_event_print_t fn, void *private_data);
 535
 536 struct bpf_prog_linfo;
 537 struct bpf_prog_info;
 538
 539 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
 540 LIBBPF_API struct bpf_prog_linfo *
 541 bpf_prog_linfo__new(const struct bpf_prog_info *info);
 542 LIBBPF_API const struct bpf_line_info *
 543 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
 544                                 __u64 addr, __u32 func_idx, __u32 nr_skip);
 545 LIBBPF_API const struct bpf_line_info *
 546 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
 547                       __u32 insn_off, __u32 nr_skip);
 548
 549 /*
 550  * Probe for supported system features
 551  *
 552  * Note that running many of these probes in a short amount of time can cause
 553  * the kernel to reach the maximal size of lockable memory allowed for the
 554  * user, causing subsequent probes to fail. In this case, the caller may want
 555  * to adjust that limit with setrlimit().
 556  */
 557 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
 558                                     __u32 ifindex);
 559 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
 560 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
 561                                  enum bpf_prog_type prog_type, __u32 ifindex);
 562 LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);
 563
 564 /*
 565  * Get bpf_prog_info in continuous memory
 566  *
 567  * struct bpf_prog_info has multiple arrays. The user has option to choose
 568  * arrays to fetch from kernel. The following APIs provide an uniform way to
 569  * fetch these data. All arrays in bpf_prog_info are stored in a single
 570  * continuous memory region. This makes it easy to store the info in a
 571  * file.
 572  *
 573  * Before writing bpf_prog_info_linear to files, it is necessary to
 574  * translate pointers in bpf_prog_info to offsets. Helper functions
 575  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
 576  * are introduced to switch between pointers and offsets.
 577  *
 578  * Examples:
 579  *   # To fetch map_ids and prog_tags:
 580  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
 581  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
 582  *   struct bpf_prog_info_linear *info_linear =
 583  *           bpf_program__get_prog_info_linear(fd, arrays);
 584  *
 585  *   # To save data in file
 586  *   bpf_program__bpil_addr_to_offs(info_linear);
 587  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
 588  *
 589  *   # To read data from file
 590  *   read(f, info_linear, <proper_size>);
 591  *   bpf_program__bpil_offs_to_addr(info_linear);
 592  */
 593 enum bpf_prog_info_array {
 594         BPF_PROG_INFO_FIRST_ARRAY = 0,
 595         BPF_PROG_INFO_JITED_INSNS = 0,
 596         BPF_PROG_INFO_XLATED_INSNS,
 597         BPF_PROG_INFO_MAP_IDS,
 598         BPF_PROG_INFO_JITED_KSYMS,
 599         BPF_PROG_INFO_JITED_FUNC_LENS,
 600         BPF_PROG_INFO_FUNC_INFO,
 601         BPF_PROG_INFO_LINE_INFO,
 602         BPF_PROG_INFO_JITED_LINE_INFO,
 603         BPF_PROG_INFO_PROG_TAGS,
 604         BPF_PROG_INFO_LAST_ARRAY,
 605 };
 606
 607 struct bpf_prog_info_linear {
 608         /* size of struct bpf_prog_info, when the tool is compiled */
 609         __u32                   info_len;
 610         /* total bytes allocated for data, round up to 8 bytes */
 611         __u32                   data_len;
 612         /* which arrays are included in data */
 613         __u64                   arrays;
 614         struct bpf_prog_info    info;
 615         __u8                    data[];
 616 };
 617
 618 LIBBPF_API struct bpf_prog_info_linear *
 619 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
 620
 621 LIBBPF_API void
 622 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
 623
 624 LIBBPF_API void
 625 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
 626
 627 /*
 628  * A helper function to get the number of possible CPUs before looking up
 629  * per-CPU maps. Negative errno is returned on failure.
 630  *
 631  * Example usage:
 632  *
 633  *     int ncpus = libbpf_num_possible_cpus();
 634  *     if (ncpus < 0) {
 635  *          // error handling
 636  *     }
 637  *     long values[ncpus];
 638  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
 639  *
 640  */
 641 LIBBPF_API int libbpf_num_possible_cpus(void);
 642
 643 struct bpf_map_skeleton {
 644         const char *name;
 645         struct bpf_map **map;
 646         void **mmaped;
 647 };
 648
 649 struct bpf_prog_skeleton {
 650         const char *name;
 651         struct bpf_program **prog;
 652         struct bpf_link **link;
 653 };
 654
 655 struct bpf_object_skeleton {
 656         size_t sz; /* size of this struct, for forward/backward compatibility */
 657
 658         const char *name;
 659         void *data;
 660         size_t data_sz;
 661
 662         struct bpf_object **obj;
 663
 664         int map_cnt;
 665         int map_skel_sz; /* sizeof(struct bpf_skeleton_map) */
 666         struct bpf_map_skeleton *maps;
 667
 668         int prog_cnt;
 669         int prog_skel_sz; /* sizeof(struct bpf_skeleton_prog) */
 670         struct bpf_prog_skeleton *progs;
 671 };
 672
 673 LIBBPF_API int
 674 bpf_object__open_skeleton(struct bpf_object_skeleton *s,
 675                           const struct bpf_object_open_opts *opts);
 676 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
 677 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
 678 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
 679 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
 680
 681 enum libbpf_tristate {
 682         TRI_NO = 0,
 683         TRI_YES = 1,
 684         TRI_MODULE = 2,
 685 };
 686
 687 #ifdef __cplusplus
 688 } /* extern "C" */
 689 #endif
 690
 691 #endif /* __LIBBPF_LIBBPF_H */